Crib to bed transition HELP

We just changed my son’s convertible crib to the toddler bed and it’s going so bad! He’s 3 years old and he’s always been an independent sleeper (has always fallen asleep without us in his room). Tonight he was relentless with asking me to keep telling him stories, keep talking, keep rubbing his back to the point of tears/melt down. After about an hour and a half we finally closed his door (which he hates) and after a minute of crying he laid down and fell asleep. I feel so terrible! Looking for any pointers/tips to make this transition better. I don’t want to get into the habit of staying in the room until he falls asleep because I know that will be hard to break!